Comprehensive Performance Evaluation Strategy for Power Battery System Based on Dynamic Weight

Abstract

New energy vehicles are an effective solution to solve the situation of carbon neutrality with carbon peaking in China. The power battery system is the key component of new energy vehicles, and its performance is directly related to the safety and cruising range. Since the performance of the battery system is affected by factors such as electrical contact stability, voltage and current characteristics, and temperature, its full life cycle performance cannot be comprehensively evaluated, resulting in inefficient prediction and protective measures. In this paper, the electrical contact stability was studied, and the evaluation index was proposed by calculating the volatility of the battery state equation. The parameters, including electrical contact stability, polynomial-based state of charge, state of health, state of consistency, and battery system temperature, constituted the performance matrix of the battery system. A comprehensive performance evaluation method for a power battery system based on dynamic weight is designed with normalized classification. Finally, the cyclic charge/discharge test experiment under the vibration state was carried out to verify the effectiveness of the method. The result showed that the method could characterize various functions and provide an intuitive and detailed evaluation for the safety prediction of a battery system.